Thorium vehicle will run 100 years on 8 grams of fuel

[PamW]

5. 100% WRONG!!

johnd83 states
Also, Thorium reactors don't "melt down". They require an outside neutron to transmute Th232 to U233. There is no "chain reaction", meaning that if the outside excitation is removed the system will stop.

The reaction that transmutes Th-232 to U-233 doesn't give you any energy.

The energy comes from a neutron impact on the U-233 thus created to yield a fission. The fission reaction gives you the energy, but also gives you fission products.

Fission products are radioactive and produce what is called "decay heat". Meltdowns are NOT caused by fission energy. In Three Mile Island and Fukushima, the fission process had stopped LONG before the meltdown. So what caused those meltdowns? The heat energy from the radioactive fission products. If you produce energy, you are causing fissions, and if you are causing fissions, you get fission products, and if you have fission products, and lose your cooling and don't cool them, you get a meltdown.

It's a bit of non-scientific hype that thorium cycle reactors are immune from meltdowns. Online removal of fission products with a liquid fuel reactor, thorium or uranium, can mitigate meltdowns by removing fission products. But just because a reactor runs on a thorium-cycle doesn't make it immune from meltdowns.

Courtesy of my alma mater, the Massachusetts Institute of Technology:

Explanation of Nuclear Reactor Decay Heat

http://mitnse.com/2011/03/16/what-is-decay-heat/

When there is a SCRAM, where all the control rods are inserted and the reactor is shutdown, the fission reactions essentially stop and the power drops drastically to about 7% of full power in 1 second. The power does not drop to zero because of the radioactive isotopes that remain from the prior fissioning of the fuel. These radioactive isotopes, also called fission products, continue to produce various types of radiation as they decay, such as gamma rays, beta particles, and alpha particles. The decay radiation then deposits most of its energy in the fuel, and this is what is referred to as decay heat.

It's all right there. When you SCRAM or shutdown the reactor, the fissions STOP; the reactor is NOT critical.

If you produced nuclear energy from PRIOR fissions, then you have fission products.

If you have fission products; you have decay heat and susceptibility to meltdowns.

PamW